This invention relates to an image information processing method and an apparatus thereof.
A video signal obtained by picking up an optical image of an object can be easily processed by such as editing, trimming and the like. Recording, reproducing and erasing a video signal can also be easily performed. These techniques have been widely used in various fields such as printing, electronic publishing, measuring and the like.
There has been an increased demand for an apparatus capable of imaging and recording an optical information such as a moving picture or an image with a higher resolution when compared to a conventional apparatus.
In a conventional apparatus for obtaining video signals, an optical image of an object picked up with an imaging lens is focussed on a photoelectric conversion section of an image pickup device, and is converted into electric image information which is time sequentially generated as serial video signals. Various image pickup tubes and solid image pickup devices have been used as the image pickup device for such an apparatus.
In order to reproduce images with high quality and resolution, it is necessary for an image pickup apparatus to generate a video signal by which an image of high quality and resolution can be reproduced. However, an image pickup apparatus using an image pickup tube has a limit for minimizing the diameter of an electron beam, and also the target capacity thereof increases as its size becomes large, resulting in a poor resolution. Furthermore, for high resolution moving images, the frequency band of a video signal becomes larger than several tens to hundreds MHz, thus posing a problem of poor 5/N. The above problems have made it difficult to obtain video signals which can reproduce images of high quality and resolution.
Moreover, in order to reproduce images with high quality and resolution by a solid state image pickup device, the device should have many pixels. However, such devices require a high clock frequency to be driven. (The clock frequency for driving the solid state image pickup device for a moving image camera reaches several hundreds MHz.) Furthermore, the capacity of the circuits to be driven inceases accordingly with the increment of the pixels. However, such a solid state image pickup device can not be realized due to the limit of the clock frequency thereof being 20 MHz.
As stated above, conventional image pickup devices could not satisfactorily generate such a video signal to provide reproduced images of high picture quality and high resolution because of the inevitable use of an image sensor for the construction thereof.
There is a demand for an image pickup apparatus to preferably generate a video signal to reproduce an image with high picture quality and high resolution. An instrument is also to be introduced which employs a video signal to record, reproduce and erase an image with high resolution, other than editing, trimming and the like by means of a reversible recording member.
In order to solve the above problems, the assignee of this application has already proposed an image pickup apparatus in which an optical iamge of an object picked up with an imaging lens is focussed on a reversible charge image recording medium on which the optical iamge is recorded and reproduced as a charge image and is erased.
Implementation of such apparatus by the assignee of this application has overcome above problems and proposed recording/reproducing image information with high resolution. However, when such information is converted into time sequential electric signals, the frequency band of the electric signals becomes extemely large. In the case of recording/reproducing an image as the image information with 4000.times.4000 pixels and converting the information into time sequential electric signals, the frequency band required for the signals becomes about 1 GHz. It is very hard to process image information with large frequency band signals. Therefore, an image information processing method and an apparatus thereof to easily process image information with extemely high resolution has been demanded.